A terrific newcomer to American gardens is a Southwest native, Agastache rupestris, also known as sunset hyssop. This drought-tolerant subshrub is worth growing for its vivid color alone, but the best surprise has been the plant's hardiness and adaptability. It flourishes in climates as diverse as the Oregon coast, southern California, northern Colorado, eastern Iowa, Philadelphia, upstate New York, and (judging by a success report from Vienna) Austria. These regions include USDA Plant Hardiness Zones 4b to 9, and a plethora of soil conditions, humidity levels, and temperature extremes.

Towards the end of summer, a dark corner of my herb patch is transformed by the flowering of an unobtrusive plant, which suddenly is covered with blue flowers. The hyssop is blooming. It flowers with the white Greek oregano, bright orange and yellow calendulas all interspersed with the clear sky blue of borage flowers and blended together with the green and gold of the ginger mint.